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Assertion : Petrified fossils contain ha...

Assertion : Petrified fossils contain hard parts of organisms.
Reason : Moulds and casts lack the remains of organisms.

A

If both the assertion and the reason are true and the reason is a correct explanation of the assertion

B

If both the assertion and reason are true but the reason is not a correct explanation of the assertion

C

If the assertion is true but the reason is false

D

If both the assertion and reason are false

Text Solution

Verified by Experts

The correct Answer is:
B
Fossils are formed when parts of dead organisms decay with the passage of time and get replaced molecule for molecule by inorganic material like iron pyrites, silica and calcium carbonates. This mineral replacement is called petrification. Hard parts like bones, shells, teeth or tronks of trees are pressured more readily than soft parts.
When material surrounding the buried organism hardens followed by decay and subsequent removal of organic matter. An exact replica of the original structure is lift behind. Such impressions are called moulds.
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